Quick Start
All the necessary
modifications to the code directly relate to the fields you want to save in a
file.
The field names
are defined in the FIELD_INDEX Enum in the bVBDB.bas module. The
field names will appear in quick tips within code windows.
Important! Change the last Enum
entry (FIELD_INDEX_MAX) to equal the LAST field you create in the
FIELD_INDEX Enum.
Next, define the
field definitions (data type, displayed field name, required, etc.) In the
CreateDataFields sub-routine in the cTable.cls class module.
The source code includes examples for most data types and an array field.
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' cTable.cls
Private Sub CreateDataFields()
' ***** MODIFY *****
' Before creating fields, modify the FIELD_INDEX Enum in bVBDB.bas.
' Use the values from the Enum as subscripts for your fields
' Note: You can assign the Constant CurrentDateTime (-1) to a date
field
' if you want the value Now() to be used as the default.
| With m_FieldDefinitions(FIELD_01) |
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.ArrayField = False |
' Is this field an array? |
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.DataType = dataBoolean |
' Specify a field data type |
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.DefaultValue = False |
' Value entered when a new record is created |
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.FieldName = "Boolean 1" |
' The name displayed to the user |
| .Index = NewFieldIndex |
' The next available index |
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.Required = False |
' Is data required? |
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.RequireUniqueEntry = False |
' Must data be unique from other records? |
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.SystemField = False |
' Is this a system field? |
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End With |
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' Code for remaining
fields not shown for brevity
' ***** END MODIFY *****
End Sub |
The
tFieldDefinitions Type defines various field properties as follows:
|
Index |
Unique index for the field |
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SystemField |
System fields should not be changed in any way.
Doing so will require you to edit a lot of code. |
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FieldName |
A string identifier for each field. This is
generally the field name displayed to the user. The name does not
have to be unique, but it should be. |
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ArrayField |
Informs VB DB that the field you have created should be
treated as an array rather than a normal variable. |
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DataType |
VB DB will validate data against the Data type you
specify for the field. Note: All fields are actually stored as variants. |
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DefaultValue |
The value initially entered into the field when a new
record is created. |
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Required |
Informs VB DB that there must be a value in this field.
For dates and numbers, the data entered can not be Null. For
strings, the data can not be an empty string. |
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RequireUniqueEntry |
If true, then a value in a field can not be duplicated in
another record. For strings, the comparison is not case-sensitive. |
Note: VB DB does not support adding additional fields after a file has
been created but most field properties can be changed using the Field
Properties dialog in the Records menu.
After adding
controls for the fields you have created, be sure to add the following line of
code to the Changed Event for TextBoxes and the Click Event for CheckBoxes:
Changed = True
The fields you create are indexed to the lblField labels.
The name you assign to the first FIELD_INDEX enum you create (not the "system"
fields) will be the
caption for lblField(0). The rest of the lblField(x) labels are indexed in
the same order as the enum.
Now the fun begins! You can
either look for places that need the code to be modified (' ***** MODIFY *****)
or do what I do — use CTRL + F5 and let VB show you where you need to
change the code. VB DB has been made as generic as possible, but you still need
to modify the code so the controls display data from the proper fields. Please
do not try to take shortcuts and use Replace All here. You may inadvertently
rename something you shouldn’t and have a debugging nightmare!
If you are not using an Array
for any of the fields, you can delete all the code having to do with a field
array. If you need more than one array, just copy the existing code and make
additional subroutines for each array. I plan to make the array fields even
more generic at some point so you won't need to do this. But for now it's
necessary.
In the Validate
Function of frmDatabase.frm, add any additional data validation you want to use. VB DB will
make sure the data entered into a field is of the correct data type, but that's
as far as it goes. For example, if you want dates to be entered within a certain range, you will
have to add the necessary code.
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